Public Economics

Public economics (or economics of the public sector) is the study of government policy through the lens of economic efficiency and equity. At its most basic level, public economics provides a framework for thinking about whether or not the government should participate in economics markets and to what extent its role should be. In order to do so, microeconomic theory is utilized to assess whether the private market is likely to provide efficient outcomes in the absence of governmental interference. Inherently, this study involves the analysis of government taxation and expenditures. This subject encompasses a host of topics including market failures, externalities, and the creation and implementation of government policy. Public economics builds on the theory of welfare economics and is ultimately used as a tool to improve social welfare.

Broad methods and topics include:

Emphasis is on analytical and scientific methods and normative-ethical analysis, as distinguished from ideology. Examples of topics covered are tax incidence,optimal taxation, and the theory of public goods.

The Journal of Economic Literature (JEL) classification codes are one way categorizing the range of economics subjects. There, Public Economics, one of 19 primary classifications, has 8 categories. They are listed below with JEL-code links to corresponding available article-preview links of The New Palgrave Dictionary of Economics Online (2008) and with similar footnote links for each respective subcategory if available:

Public goods, or collective consumption goods, exhibit two properties; non-rivalry and non-excludability. Something is non-rivaled if one person's consumption of it does not deprive another person, (to a point) a firework display is non-rivaled - since one person watching a firework display does not prevent another person from doing so. Something is non-excludable if its use cannot be limited to a certain group of people. Again, since one cannot prevent people from viewing a firework display it is non-excludable. Conceptually, another example of public good is the service that is provided by law enforcement organizations, such as sheriffs and police. Typically, cities and towns are served by only one police department, and the police department serves all of the people within its jurisdiction.

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